The use of dalbavancin as a catheter lock solution must be addressed in depth before implementation in clinical practice. We assessed whether a heparin-based dalbavancin lock solution could be frozen in single-dose vials for 6 months without affecting its bioactivity against biofilms of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Staphylococcus epidermidis (MRSE). Over 6 months, we tested the bioactivity of a frozen solution of dalbavancin (≈1 mg/ml) plus heparin (60 IU) in terms of CFU counts and metabolic activity against biofilms of Staphylococcus aureus ATCC 43300 (MRSA) and Staphylococcus epidermidis ATCC 35984 (MRSE). The Anti-Xa assay was also performed to assess whether the anticoagulant activity of heparin was reduced under freezing. Every month, we compared the mean value of each variable with that obtained at baseline (before freezing, month 0) using both clinical criteria (values were within 25% of the baseline value) and statistical criteria (linear mixed models). At the end of the experiment (month 6), neither a clinically nor a statistically significant reduction in the bioactivity of dalbavancin-heparin solution was observed in terms of CFU counts and metabolic activity against biofilm of MRSA. Regarding MRSE, considering the clinical criteria, neither CFU counts nor metabolic activity decreased significantly. However, the reduction was statistically significant for all variables. Anti-Xa values (mean [standard deviation] international units per milliliter) for heparin in combination with dalbavancin were within 25% of the heparin-water value. A heparin-based dalbavancin lock solution can be frozen for up to 6 months with no effect on its bioactivity against MRSA and MRSE biofilms.

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评估基于肝素的达巴万星锁溶液的生物活性的体外研究

在临床实践中实施之前，必须深入探讨达巴万星作为导管锁定溶液的用途。我们评估了基于肝素的达巴万星锁定溶液是否可以在单剂量小瓶中冷冻6个月而不会影响其对耐甲氧西林金黄色葡萄球菌（MRSA）和耐甲氧西林金黄色葡萄球菌（MRSE）生物膜的生物活性。在6个月的时间里，我们测试了达巴万星（≈1mg / ml）加肝素（60 IU）冷冻溶液的生物活性，涉及CFU计数以及针对金黄色葡萄球菌ATCC 43300（MRSA）和表皮葡萄球菌的生物膜的代谢活性。ATCC 35984（MRSE）。还进行了抗Xa分析以评估肝素的抗凝活性在冷冻下是否降低。每个月，我们使用临床标准（值在基线值的25％以内）和统计标准（线性混合模型）将每个变量的平均值与在基线（冷冻前，第0个月）获得的平均值进行比较。在实验结束时（第6个月），就CFU计数和针对MRSA生物膜的代谢活性而言，达巴万星-肝素溶液的生物活性未见临床或统计学显着下降。关于MRSE，考虑到临床标准，CFU计数和代谢活性均未显着下降。但是，对于所有变量，减少量在统计上均具有显着意义。肝素与达巴万星合用的抗Xa值（平均[标准偏差]国际单位/毫升）在肝素-水值的25％以内。基于肝素的达巴万星锁定溶液可以冷冻长达6个月，而对MRSA和MRSE生物膜的生物活性没有影响。